Its not that difficult to workout the invoice if you have the retail price. Markup percentages are almost the same from previous year. Use a spreadsheet and the 2010 invoice price and apply the % for new items.

Base invoice price is 8% less than suggested retail price rounded off.
e.g. xDrive50i retail price is $59,275 and 8% less of that is $54,333 rounded off to $54,350 being the invoice.